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1.
A. P. Tyutnev R. Sh. Ikhsanov E. L. Grin’ G. P. Safonov A. I. Kononenko A. M. Sorokin I. V. Rudenko 《Polymer Science Series A》2006,48(11):1190-1195
A general theory of the phenomenon of recovered voltage in polymers was considered on the basis of representation of an actual poling process by a discrete set of Debye relaxators. Examples of numerical solution of the direct and inverse problems are given. A correlation expression between intentionally aged polymer specimens and recovered-voltage curves was proposed for use in the assessment of the material state of a polymer under actual service conditions. It was shown that it is sufficient to restrict consideration to three relaxation processes in analysis of the phenomenon. 相似文献
2.
The solid-liquid interface motion of NaBi(WO4)2 (NBWO) melt crystal growth is observed in an in situ system, in which the whole processes of interface transition from fiat interface and cellular to dendrite are visualized. The spacing of the dendrite under smaller temperature gradient turns out to be larger than that under larger temperature gradient, which is found to be sensitive to the temperature distribution. The mechanism of dendrite growth of NBWO is studied based on the model of the growth units of anion coordination polyhedra. The { 001} face has two apex links, so it shows higher stability and has high growth rate and forms the arm of dendrite, whereas the {010} face has only one apex link, and thus shows relative slower growth rate and firstly forms the branches. 相似文献
3.
In Situ Observation of Skeletal Shape Transition during BaB2O4 Crystal Growth in High-Temperature Solution
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The transition from a fiat solid-liquid interface to a skeletal shape during BaB2O4 (BBO) single crystal growth in Li2B4O7 flux is observed in real time by an optical high-temperature in-situ observation system. The movement of crystal step is also investigated. The observation results demonstrate that the steps propagate along and parallel to the fiat interface when the crystal size is small. Nevertheless, they will ‘bend' close to the face centre if the crystal size becomes greater. Atomic force microscopy reveals that more deposition places near the face centre give rise to the bending of advancing steps and thus the formation of a vicinal interface structure. Measurements of step velocity show that the velocity keeps nearly constant at different moments for one specific step, whereas the step on a newly formed layer advanced faster than that on a previously formed one when the crystal size is larger than 210μm or so. Thus interracial morphological instability occurs and a skeletal interface is obtained. 相似文献
4.
We generalize a method for determination of time scales of nonstationary diffusion in a one-dimensional medium. The time of relaxation to a stationary non-equilibrium density of substance in a system with a source, a sink, and an arbitrary potential profile are obtained and studied in detail. A few specific examples are considered. 相似文献
5.
B. B. Damaskin O. A. Baturina V. A. Safonov N. V. Safonov 《Russian Journal of Electrochemistry》2003,39(6):685-691
Effect of the electrode potential on the coadsorption of two organic substances is studied using a set of two mixed Frumkin isotherms and a model of three parallel capacitors in conditions where in the absence of an electric field this system has seven solutions. It is shown that only four of these solutions may correspond to realizable adsorption states. Effect of the electrode potential on the number of possible solutions of the isotherm set, the number of realizable adsorption states, as well as on the composition and properties of a surface layer is considered. 相似文献
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Within the semimicroscopic approach based on the random-phase approximation that takes exactly into account a single-particle continuum and on a phenomenological inclusion of the fragmentation effect, it is proposed to describe the strength functions for charge-exchange giant dipole resonances and cross sections for photoabsorption and for partial “direct + semidirect” (γ, p) reactions in the vicinity of a giant E1 resonance with allowance for the isospin-splitting effect. The results of the calculations performed for some magic and semimagic nuclei without resort to free parameters are compared with available experimental data. 相似文献
8.
EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
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血橙中微量元素的测定 总被引:2,自引:0,他引:2
采用电感耦合等离子体原子发射光谱仪(ICP-AES),对血橙果肉汁、皮、籽中10种微量元素进行了测定。结果表明,血橙果肉汁、皮、籽中含有Ca、Mg、Fe、Zn、Mn、Cu、Ni等丰富的人体必需微量元素,且血橙果皮、籽中的微量元素含量普遍高于果肉汁中的微量元素的含量,这为血橙药效功能的进一步研究和资源综合开发利用提供一定的科学依据。 相似文献